Guide structure for telescopic rail assembly

ABSTRACT

Guide structure for telescopic rail assembly, including an outer slide rail, an inner slide rail, a protective section, a pair of first slopes, a pair of second slopes and a pair of third slopes. The outer slide rail is disposed on a cabinet body, while the inner slide rail is disposed on a drawer and slidably nested in the outer slide rail. A ball bearing is disposed between the outer and inner slide rails to facilitate sliding thereof. The protective section is formed with the first and second slopes and positioned between front end of the ball bearing and front end of the outer slide rail. Rear end of the inner slide rail is formed with the third slopes. After the drawer is drawn out of the cabinet body, by means of the first, second and third slopes, the inner slide rail can be easily nested into the outer slide rail without colliding the ball bearing, whereby the ball bearing will not jump away or damage.

BACKGROUND OF THE INVENTION

[0001] The present invention is related to a sliding means disposed between two articles, and more particularly to a slide rail assembly applied to drawers and file cabinets.

[0002] Conventionally, two slide rails are provided between a drawer and a cabinet body. One of the slide rail is slidably nested in the other, whereby the drawer can be smoothly drawn and pushed within the cabinet body.

[0003] Referring to FIG. 1, the slide rails A, B are channel bodies formed with a U-shaped cross-section and having a bottom wall and two side walls. The larger slide rail A is equipped with internal ball bearing C and the smaller slide rail A is nested in the larger slide rail A. Two side walls of the ball bearing C are positioned between the side walls of the slide rails A and B. By means of the balls of the side walls of the ball bearing and the cooperative spherical rails of the side walls of the slide rails A and B, the drawer can be easily drawn and pushed without producing great noise.

[0004] Sometimes it is necessary for a user to draw the drawer out of the cabinet body. Under such circumstance, due to frictional force, the front end of the ball bearing C will be dragged toward outer end of the slide rail A and stopped by a bearing stopper disposed near the outer end. When the user again places the drawer into the cabinet body, it is necessary for the user to aim the end of the slide rail B at the end of the slide rail A for successfully assemble the drawer with the cabinet body. When assembled, in order to prevent the ball bearing C from being collided and damaged by the end of the slide rail B, a protective sheath D is disposed at the outer end of the slide rail A. The protective sheath D has a cross-section substantially corresponding to the cross-section of the slide rail A. The protective sheath D not only serves to stop the ball bearing C, but also is able to guide the slide rail B into the ball bearing C.

[0005] In the above structure, the outer end face of the protective sheath D is flush with the outer end face of the slide rail A. In addition, the inner faces of the bottom wall and side walls of the protective sheath D are normal to the outer end face thereof. Also, the inner faces of the bottom wall and side walls of the slide rail B are normal to the outer end face thereof. Therefore, when assembled, the slide rail B is very likely to clog in the protective sheath D, especially when a heavy article is loaded in the drawer.

[0006] Another situation also often takes place. That is, the ball bearing C is not adjoined with the protective sheath D so that after the slide rail B is inserted into the protective sheath D, due to frictional force, the outer end of the slide rail B abuts against the outer end of the ball bearing C. The user can hardly check this and will often further push the drawer inward. At this time, the ball bearing C will be driven and pushed by the slide rail B inward until the ball bearing C is stopped. In the case that the user further pushes in the drawer, the slide rail B will compress and deform the ball bearing C or make the ball bearing C jump away.

SUMMARY OF THE INVENTION

[0007] It is therefore a primary object of the present invention to provide a guide structure for telescopic rail assembly. The guide structure enables a user to easily and smoothly assemble a drawer with a cabinet body without accurately aiming the inner slide rail at the outer slide rail.

[0008] It is a further object of the present invention to provide the above guide structure by which when assembling the drawer with the cabinet body, the inner slide rail will not collide the ball bearing, whereby the ball bearing will not jump away or be deformed. Therefore, the using life of the rail assembly is prolonged.

[0009] The present invention can be best understood through the following description and accompanying drawings wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a perspective view of parts of a conventional telescopic rail assembly;

[0011]FIG. 2 is a perspective view of a first embodiment of the guide structure of the present invention;

[0012]FIG. 3 is a front view of the first embodiment of the guide structure of the present invention;

[0013]FIG. 4 is a perspective view of a second embodiment of the guide structure of the present invention;

[0014]FIG. 5 is a perspective view of a third embodiment of the guide structure of the present invention;

[0015]FIG. 6 is a perspective view of the protective section of the third embodiment of the guide structure of the present invention; and

[0016]FIG. 7 is a top view of the protective section of the third embodiment of the guide structure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Please refer to FIGS. 2 and 3. The guide structure 1 for telescopic rail assembly of the present invention includes an outer slide rail 12, an inner slide rail 14, a protective section 16, a pair of first slopes 62, a pair of second slopes 64 and a pair of third slopes 42. In addition, a ball bearing 13 which is a channel body having U-shaped cross-section is disposed between the outer slide rail 12 and the inner slide rail 14.

[0018] The outer slide rail 12 is a channel body with a certain length. The outer slide rail 12 has a bottom wall and two side walls. Each side wall has C-shaped cross-section and serves as a spherical ball rail. The outer side of the bottom wall of the outer slide rail 12 is laid on a cabinet body.

[0019] The inner slide rail 14 is a channel body with a certain length. The inner slide rail 14 has a bottom wall and two side walls. Each side wall has C-shaped cross-section and serves as a spherical ball rail. The outer side of the bottom wall of the inner slide rail 14 is laid on a drawer.

[0020] The outer side of the bottom wall of the ball bearing 13 corresponds to the inner side of the bottom wall of the outer slide rail 12. The ball bearing 13 is disposed in the outer slide rail 12. Several balls are arranged on the side walls of the ball bearing 13.

[0021] The inner slide rail 14 is symmetrically laid in the outer slide rail 12 with the side walls of the ball bearing 13 positioned between the side walls of the outer and inner slide rails 12, 14.

[0022] The protective section 16 is a channel body with a certain length. The protective section 16 has a cross-section corresponding to the outer slide rail 12. The outer side of the bottom wall of the protective section 16 corresponds to the inner side of the bottom wall of the outer slide rail 12. The protective section 16 is fixed in the outer slide rail 12 at a predetermined portion thereof between the front end of the outer slide rail 12 and the front end of the ball bearing 13. The protective section 16 has the first and second slopes 62, 64.

[0023] Each first slope 62 is formed at the front end of each side wall of the protective section 16 in such a manner that each first slope 62 is inclined from inner side to outer side toward the side wall of the outer slide rail 12. The outer end of each first slope 62 is spaced from the front end of the outer slide rail 12 by a predetermined distance.

[0024] Each second slope 64 is formed on the shoulder section of the front end of the bottom wall of the protective section 16 in such a manner that each second slope 64 is inclined from inner side to outer side toward the bottom wall of the outer slide rail 12. The outer end of each second slope 64 is spaced from the front end of the outer slide rail 12 by a predetermined distance.

[0025] Each third slope 42 is formed at the rear end of each side wall of the inner slide rail 14 in such a manner that each third slope 42 inclinedly outward extends toward the shoulder section of the bottom wall of the inner slide rail 14.

[0026] The outer ends of the first and second slopes 62, 64 are spaced from the front end of the outer slide rail 12. Therefore, when nesting the inner slide rail 14 disposed on a drawer 14 into the outer slide rail 12 disposed on the cabinet body, the inner slide rail 14 has larger freeness and can be easily extended into the outer slide rail 12. Then, by means of the guiding of the first, second and third slopes 62, 64, 42, the assembly can be easily completed.

[0027]FIG. 4 shows another embodiment of the present invention, in which the protective section 16 is not disposed on the outer slide rail 12. Instead, the protective section 16 is provided with a connecting section 66 formed by two plate bodies inward extending from the rear ends of side walls of the protective section 16 by a predetermined length. Each plate body is formed with perforations corresponding to the balls of the ball bearing 13. By means of the connecting section 66, the protective section 16 can be connected with the ball bearing 13 and moved along with the ball bearing 13. In addition, a stop lug 122 projects from the bottom wall of the outer slide rail 12 and is spaced from the front end thereof by a predetermined distance. The stop lug 122 is positioned between the front end of the protective section 16 and the front end of the outer slide rail 12. When the inner slide rail 14 is extended and detached from the outer slide rail 12, the stop lug 122 serves to stop the protective section 16 and space the outer ends of the first and second slopes 62, 64 from the front end of the outer slide rail 12 by a predetermined distance. Therefore, the free space remains to facilitate assembly and ball bearing 13 is protected.

[0028] The guide structure for telescopic rail assembly of the present invention has the following advantages:

[0029] 1. The outer ends of the first and second slopes 62, 64 are spaced from the front end of the outer slide rail 12. By means of the first, second and third slopes 62, 64, 42, the assembly is facilitated.

[0030] 2. By means of the protective section 16 connected with the ball bearing 13, when nesting the inner slide rail 14 into the outer slide rail 12, the inner slide rail 14 will not abut against and push the front end of the ball bearing 13. Therefore, the ball bearing 13 is protected from being damaged.

[0031] 3. The protective section 16 is connected with the ball bearing 13 and movable along therewith. Once the inner slide rail 14 is extended into the outer slide rail 12, no matter whether the inner slide rail 14 is immediately nested into the ball bearing 13, eventually the inner slide rail 14 will extend into the ball bearing 13.

[0032] In FIG. 4, the protective section 16 outward extends from front end of the ball bearing 13. This can achieve the same object of the present invention.

[0033] In the above embodiment, the first and second slopes 62, 64 intersect the inner faces of the side walls and bottom wall of the outer slide rail 12. This achieves better freeness of space.

[0034] With respect to the conventional protective sheath D, the inner side of bottom wall of the protective sheath D is provided with a rectangular block projecting therefrom by a certain height. A corresponding engaging plate (not shown) is disposed on a predetermined portion of inner face of bottom wall of the slide rail B for engaging with the rectangular block and preventing the drawer from dropping from the cabinet body. When pressing the engaging plate, the drawer can be detached from the cabinet body. However, when assembling the two slide rails A, B, the vertical face of the front end of the rectangular block will obstruct the slide rail B.

[0035] Therefore, further referring to FIGS. 5 to 7, in the case that a predetermined portion of the inner side of bottom wall of the protective section 16 is provided with an engaging block 161 and the protective section 16 is fixed on the outer slide rail 12 with the front end face flush with the front end face of the outer slide rail 12, the first slopes 62 are formed on the middle portions of inner faces of side walls of the protective section 16. The second slopes 64 are formed on the front end of the engaging block 161, the second slopes 64 being inclined from inner side to outer side toward the bottom wall of the protective section 16 and linked and formed a slop. Moreover, the rear end of each side wall of the protective section 16 is respectively formed with a split 68 corresponding to the front end of each side wall of the ball bearing 13. The split 68 can be a Y-shaped notch. When the inner slide rail 14 is extended and detached from the outer slide rail 12, the ball bearing 13 is driven and clamped in the splits 68. Therefore, when the inner slide rail 14 is nested into the outer slide rail 12, the inner slide rail 14 will not abut against and push the front end of the ball bearing 13 so that the ball bearing 13 is protected from being damaged.

[0036] In the above structure, the second slopes 64 can be omitted and only by means of the third slopes 42, the same object can be achieved.

[0037] Alternatively, the third slopes 42 can be omitted and the outer ends of the first and second slopes 62, 64 are spaced from the front end of the outer slide rail 12 by a predetermined distance. This can also have better freeness of space and achieve the object of the present invention.

[0038] The above embodiments are only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiments can be made without departing from the spirit of the present invention. 

What is claimed is:
 1. Guide structure for telescopic rail assembly, comprising an outer slide rail, a protective section and an inner slide rail, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; and the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail at a predetermined portion thereof between the front end of the outer slide rail and the front end of the ball bearing, said guide structure being characterized in that: the protective section is formed with a pair of first slopes and a pair of second slopes; each first slope is formed at the front end of each side wall of the protective section in such a manner that each first slope is inclined from inner side to outer side toward the side wall of the outer slide rail; each second slope is formed on the shoulder section of the front end of the bottom wall of the protective section in such a manner that each second slope is inclined from inner side to outer side toward the bottom wall of the outer slide rail; and the outer ends of the first and second slopes are spaced from the front end of the outer slide rail by a predetermined distance.
 2. Guide structure for telescopic rail assembly, comprising an outer slide rail, a protective section and an inner slide rail, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; and the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail at a predetermined portion thereof between the front end of the outer slide rail and the front end of the ball bearing, said guide structure being characterized in that: the protective section is formed with a pair of first slopes and the inner slide rail is formed with a pair of third slopes; each first slope is formed at the front end of each side wall of the protective section in such a manner that each first slope is inclined from inner side to outer side toward the side wall of the outer slide rail, the outer end of the first slope being spaced from the front end of the outer slide rail by a predetermined distance; and each third slope is formed at the rear end of each side wall of the inner slide rail in such a manner that each third slope inclinedly outward extends toward the shoulder section of the bottom wall of the inner slide rail.
 3. Guide structure for telescopic rail assembly, comprising an outer slide rail, an inner slide rail, a protective section and a stop section, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail between the front end of the outer slide rail and the front end of the ball bearing; and the stop section is disposed at a predetermined portion of the outer slide rail for stopping the ball bearing from slipping out of the front end of the outer slide rail, said guide structure being characterized in that: the protective section is fixed at the front end of the ball bearing and is movable along with the ball bearing, whereby when nesting the inner slide rail into the outer slide rail, the inner slide rail will not abut against and push the front end of the ball bearing so that the ball bearing is protected from being damaged and the assembly can be truly completed; the protective section is formed with a pair of first slopes and a pair of second slopes; each first slope is formed at the front end of each side wall of the protective section in such a manner that each first slope is inclined from inner side to outer side toward the side wall of the outer slide rail; each second slope is formed on the shoulder section of the front end of the bottom wall of the protective section in such a manner that each second slope is inclined from inner side to outer side toward the bottom wall of the outer slide rail; and when the protective section is stopped by the stop section, the outer ends of the first and second slopes are spaced from the front end of the outer slide rail by a predetermined distance.
 4. Guide structure for telescopic rail assembly, comprising an outer slide rail, an inner slide rail, a protective section and a stop section, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail between the front end of the outer slide rail and the front end of the ball bearing; and the stop section is disposed at a predetermined portion of the outer slide rail for stopping the ball bearing from slipping out of the front end of the outer slide rail, said guide structure being characterized in that: the protective section is fixed at the front end of the ball bearing and is movable along with the ball bearing, whereby when nesting the inner slide rail into the outer slide rail, the inner slide rail will not abut against and push the front end of the ball bearing so that the ball bearing is protected from being damaged and the assembly can be truly completed; the protective section is formed with a pair of first slopes; the inner slide rail is formed with a pair of third slopes; each first slope is formed at the front end of each side wall of the protective section in such a manner that each first slope is inclined from inner side to outer side toward the side wall of the outer slide rail, whereby when the protective section is stopped by the stop section, the outer end of the first slope is spaced from the front end of the outer slide rail by a predetermined distance; and each third slopes is formed at the rear end of each side wall of the inner slide rail in such a manner that each third slope inclinedly outward extends toward the shoulder section of the bottom wall of the inner slide rail.
 5. Guide structure for telescopic rail assembly as claimed in claim 3, wherein a connecting section is disposed at a predetermined portion of the rear end of the protective section for connecting with the ball bearing.
 6. Guide structure for telescopic rail assembly as claimed in claim 4, wherein a connecting section is disposed at a predetermined portion of the rear end of the protective section for connecting with the ball bearing.
 7. Guide structure for telescopic rail assembly as claimed in claim 5, wherein the connecting section is formed by two plate bodies inward extending from the rear ends of the side walls of the protective section by a predetermined length, each plate body being formed with perforations corresponding to and fitted on the balls of the ball bearing.
 8. Guide structure for telescopic rail assembly as claimed in claim 6, wherein the connecting section is formed by two plate bodies inward extending from the rear ends of the side walls of the protective section by a predetermined length, each plate body being formed with perforations corresponding to and fitted on the balls of the ball bearing.
 9. Guide structure for telescopic rail assembly as claimed in claim 3, wherein the protective section is such formed that the protective section outward extends from the front end of the ball bearing.
 10. Guide structure for telescopic rail assembly as claimed in claim 4, wherein the protective section is such formed that the protective section outward extends from the front end of the ball bearing.
 11. Guide structure for telescopic rail assembly as claimed in claim 3, wherein the stop section is a projecting lug disposed on the bottom wall of the outer slide rail.
 12. Guide structure for telescopic rail assembly as claimed in claim 4, wherein the stop section is a projecting lug disposed on the bottom wall of the outer slide rail.
 13. Guide structure for telescopic rail assembly as claimed in claim 1, wherein the first and second slopes intersect the inner faces of the side walls and the bottom wall of the outer slide rail.
 14. Guide structure for telescopic rail assembly as claimed in claim 3, wherein the first and second slopes intersect the inner faces of the side walls and the bottom wall of the outer slide rail.
 15. Guide structure for telescopic rail assembly as claimed in claim 2, wherein the first slopes intersect the inner faces of the side walls of the outer slide rail.
 16. Guide structure for telescopic rail assembly as claimed in claim 4, wherein the first slopes intersect the inner faces of the side walls of the outer slide rail.
 17. Guide structure for telescopic rail assembly, comprising an outer slide rail, a protective section and an inner slide rail, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer, an engaging plate being disposed on a predetermined portion of inner face of bottom wall of the inner slide rail; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; and the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail at a predetermined portion thereof between the front end of the outer slide rail and the front end of the ball bearing, the front end of the protective section being flush with the front end of the outer slide rail, a projecting rectangular engaging block being disposed on a predetermined portion of inner face of bottom wall of the protective section for engaging with the engaging plate and preventing the drawer from detaching from the cabinet body, when pressing the engaging plate, the drawer being drawable out of the cabinet body, said guide structure being characterized in that: the protective section is fixed on the outer slide rail and formed with a pair of first slopes and a pair of second slopes; each first slope is formed on the middle portion of the inner face of the side wall of the protective section, each first slope being inclined from inner side to outer side toward the side wall of the outer slide rail; and each second slope is formed on the front end of the engaging block, each second slope being inclined from inner side to outer side toward the bottom wall of the protective section and linked and formed a slop.
 18. Guide structure for telescopic rail assembly, comprising an outer slide rail, a protective section and an inner slide rail, wherein: the outer and inner slide rails are channel bodies with predetermined length, each of the outer and inner slide rails having a bottom wall and two side walls, each side wall having C-shaped cross-section and serving as a spherical ball rail, outer sides of the bottom walls of the outer and inner slide rails being respectively fixed on a cabinet body and a drawer, an engaging plate being disposed on a predetermined portion of inner face of bottom wall of the inner slide rail; the ball bearing is a channel body having U-shaped cross-section and disposed between the outer and inner slide rails, several balls being arranged on side walls of the ball bearing; an outer side of bottom wall of the ball bearing corresponds to the inner side of the bottom wall of the outer slide rail, the ball bearing being disposed in the outer slide rail, the inner slide rail being symmetrically laid in the outer slide rail with the side walls of the ball bearing positioned between the side walls of the outer and inner slide rails; and the protective section is a channel body with a certain length, the protective section having a cross-section corresponding to the outer slide rail, an outer side of bottom wall of the protective section corresponding to the inner side of the bottom wall of the outer slide rail, the protective section being fixed in the outer slide rail at a predetermined portion thereof between the front end of the outer slide rail and the front end of the ball bearing, the front end of the protective section being flush with the front end of the outer slide rail, a projecting rectangular engaging block being disposed on a predetermined portion of inner face of bottom wall of the protective section for engaging with the engaging plate and preventing the drawer from detaching from the cabinet body, when pressing the engaging plate, the drawer being drawable out of the cabinet body, said guide structure being characterized in that: the protective section is fixed on the outer slide rail and formed with a pair of first slopes, the inner slide rail being formed with a pair of third slopes; each first slope is formed on the middle portion of the inner face of the side wall of the protective section, each first slope being inclined from inner side to outer side toward the side wall of the outer slide rail; and each third slope is formed at the rear end of each side wall of the inner slide rail in such a manner that each third slope inclinedly outward extends toward the shoulder section of the bottom wall of the inner slide rail.
 19. Guide structure for telescopic rail assembly as claimed in claim 17, wherein the rear end of each side wall of the protective section is respectively formed with a split corresponding to the front end of each side wall of the ball bearing, whereby when the inner slide rail is extended and detached from the outer slide rail, the ball bearing is driven and clamped in the splits.
 20. Guide structure for telescopic rail assembly as claimed in claim 18, wherein the rear end of each side wall of the protective section is respectively formed with a split corresponding to the front end of each side wall of the ball bearing, whereby when the inner slide rail is extended and detached from the outer slide rail, the ball bearing is driven and clamped in the splits.
 21. Guide structure for telescopic rail assembly as claimed in claim 19, wherein the split is a Y-shaped notch.
 22. Guide structure for telescopic rail assembly as claimed in claim 20, wherein the split is a Y-shaped notch. 